Rock Identifier

Category

Sedimentary Or Igneous (Secondary Formation)

Browse sedimentary or igneous (secondary formation) specimens identified by the Rock Identifier community.

Chert / Flint (with quartz or calcite inclusion) (Silicon dioxide (SiO2)) — sedimentary

Chert / Flint (with quartz or calcite inclusion)

Silicon dioxide (SiO2)

Quartz Geode (Silicon dioxide (SiO2)) — mineral

Quartz Geode

Silicon dioxide (SiO2)

Quartz (Druzy) (Silicon Dioxide (SiO2)) — mineral

Quartz (Druzy)

Silicon Dioxide (SiO2)

Druzy Quartz on Host Rock (Silicon Dioxide (SiO2) with various iron-oxide inclusions) — mineral

Druzy Quartz on Host Rock

Silicon Dioxide (SiO2) with various iron-oxide inclusions

Limonite (Iron-rich Siltstone / Sandstone base) (Hydrous ferric oxide mixture (FeO(OH)·nH2O)) — sedimentary

Limonite (Iron-rich Siltstone / Sandstone base)

Hydrous ferric oxide mixture (FeO(OH)·nH2O)

Satin Spar (Selenite) (Gypsum (CaSO4·2H2O)) — mineral

Satin Spar (Selenite)

Gypsum (CaSO4·2H2O)

Bloodstone (Heliotrope) (Silicon Dioxide (SiO2) with inclusions of Chlorite or Actinolite) — sedimentary

Bloodstone (Heliotrope)

Silicon Dioxide (SiO2) with inclusions of Chlorite or Actinolite

Chert (with Quartz Vein) (Chert (Siliceous sedimentary rock, predominantly Microcrystalline Quartz SiO2)) — sedimentary

Chert (with Quartz Vein)

Chert (Siliceous sedimentary rock, predominantly Microcrystalline Quartz SiO2)

Clear Quartz (Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Blue Apatite (Apatite - Ca5(PO4)3(F,Cl,OH)) — mineral

Blue Apatite

Apatite - Ca5(PO4)3(F,Cl,OH)

Chalcedony (Grey/White Agate) (Silicon Dioxide (SiO₂)) — mineral

Chalcedony (Grey/White Agate)

Silicon Dioxide (SiO₂)

Calcite (Calcium Carbonate (CaCO3)) — mineral

Calcite

Calcium Carbonate (CaCO3)

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Firewood (Wood Log) (Lignum (Plant tissue composed of cellulose and lignin)) — Organic (Non-geological)

Firewood (Wood Log)

Lignum (Plant tissue composed of cellulose and lignin)

Organic (Non-geological)

Quartz (Iron-stained) (Silicon Dioxide (SiO2)) — mineral

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Basalt with Quartz Veining (Basalt (Mafic Extrusive Igneous Rock) with SiO2 (Silicon Dioxide) veins) — igneous

Basalt with Quartz Veining

Basalt (Mafic Extrusive Igneous Rock) with SiO2 (Silicon Dioxide) veins

Chalcedony (Agate) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (Agate)

Silicon Dioxide (SiO2)

Fluorite Tower (Fluorite (Calcium Fluoride - CaF2)) — mineral

Fluorite Tower

Fluorite (Calcium Fluoride - CaF2)

Magnetite / Iron Ore (Magnetite (Fe3O4)) — mineral

Magnetite / Iron Ore

Magnetite (Fe3O4)

Quartz (Silicon dioxide (SiO2)) — Mineral

Quartz

Silicon dioxide (SiO2)

Gold Nugget (Native Gold (Au)) — mineral

Gold Nugget

Native Gold (Au)

Banded Chert (with Quartz Vein) (Microcrystalline Silica (SiO2)) — sedimentary

Banded Chert (with Quartz Vein)

Microcrystalline Silica (SiO2)

Prehnite (Prehnite (Ca2Al2Si3O10(OH)2)) — mineral

Prehnite

Prehnite (Ca2Al2Si3O10(OH)2)

Magnetite (Iron Ore) (Magnetite (Fe3O4)) — mineral

Magnetite (Iron Ore)

Magnetite (Fe3O4)

Milky Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Sulfur (Native Sulfur (S8)) — mineral

Sulfur

Native Sulfur (S8)

Ferruginous Quartz (Silicon Dioxide (SiO2) with Iron Oxide inclusions) — mineral

Ferruginous Quartz

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Milky Quartz (Vein Quartz) (Silicon Dioxide (SiO2)) — mineral

Milky Quartz (Vein Quartz)

Silicon Dioxide (SiO2)

Magnetite (potentially Hematite-rich) (Magnetite (Fe3O4)) — mineral

Magnetite (potentially Hematite-rich)

Magnetite (Fe3O4)

Agate (Grey Agate Slice) (Microcrystalline Quartz (SiO2)) — mineral

Agate (Grey Agate Slice)

Microcrystalline Quartz (SiO2)

Unidentifiable Specimen (Undetermined) — Unknown

Unidentifiable Specimen

Undetermined

Pyrite (Fool's Gold) (Iron Sulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Clear Quartz (Rock Crystal) (Quartz (Silicon Dioxide, SiO2)) — mineral

Clear Quartz (Rock Crystal)

Quartz (Silicon Dioxide, SiO2)

Quartz Vein in Host Rock (Silicon Dioxide (SiO2) within Sedimentary or Igneous Matrix) — igneous

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within Sedimentary or Igneous Matrix

Geode with Iron-Stained Quartz/Calcite (Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3) in Sedimentary Matrix) — sedimentary

Geode with Iron-Stained Quartz/Calcite

Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3) in Sedimentary Matrix

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hematite (Hematite, Iron(III) oxide (Fe2O3)) — mineral

Hematite

Hematite, Iron(III) oxide (Fe2O3)

Sandstone with Liesegang Rings (Arenite with secondary Iron oxide (Limonite/Goethite) precipitation) — sedimentary

Sandstone with Liesegang Rings

Arenite with secondary Iron oxide (Limonite/Goethite) precipitation

Basalt (Basalt (Aphanitic Mafic Igneous Rock)) — igneous

Basalt

Basalt (Aphanitic Mafic Igneous Rock)

Diamond Druzy (Crystalline Diamond) (Carbon (C)) — mineral

Diamond Druzy (Crystalline Diamond)

Carbon (C)

Gold Nugget (Native Gold (Au)) — mineral

Gold Nugget

Native Gold (Au)

Granite (weathered/river-tumbled) (Granite (Plutonic Igneous Rock)) — Igneous Rock

Granite (weathered/river-tumbled)

Granite (Plutonic Igneous Rock)